Manicures feel like such a luxury mainly because they are purely decorative; they don’t fulfill any sort of necessity and they’re not particularly functional. But as Lucie Davis, a jewelry design student at Central St. Martins in London suggests, they very easily could be useful. Especially if you’re the type who’s constantly misplacing your train card.

For her final graduate project, Davis designed a set of acrylic nails that also doubles as an Oyster card, the plastic card with which Londoners pay for rides on the tube. It’s as simple as it is genius: Davis took the RFID microchip built in to the Oyster card and embedded it into a full set of acrylic nails. The card reader on the turnstile picks up the chip just as it would in a plastic card. Instead of fishing through a purse or pulling out a wallet, Davis taps her nails onto the card reader and walks on through.

Davis came up with the project in response to a class assignment that asked students to create work inspired by their everyday activities. “I was hoping that this idea would make everyone’s next commute a little more thoughtful and enjoyable rather than our usual mindless ones,” Davis told the blog for WAH Nails, a salon in London. “I like to think of my work as a 21st-century update to the traditional keepsake. It’s about finding a fresh new perspective on things, providing more meaning in a world we may take for granted, and (hopefully) changing the way we think in a positive light.”

Right now the blue-and-white Oyster card nails are just a concept, but with any luck they’ll hit the market soon–hopefully with versions for all major city’s transportation systems. Vignelli-themed nails, anyone?